1. Field of the Invention
The present invention relates to an image protecting film useful for imparting gloss to a printed image formed by printing or various recording methods, or for protecting such a printed image from water and light. More particularly, the present invention relates to an image protecting film suitable for protecting a printed image formed by an ink jet recording method.
2. Discussion of the Background
An ink jet recording system has found a rapid spread in recent years because of its merits such that it produces little noise, makes multi-coloring possible, and simplifies formation of a large image, and the running cost is small.
The recording medium to be used for the ink jet recording includes, in addition to ordinary paper and coated paper, a plastic film having a porous surface layer, and a non-porous hydrophobic plastic film having an ink accepting layer comprising organic or inorganic fine particles and a binder resin coated thereon.
As the recording liquid for such ink jet recording, an aqueous type is mainly used from the viewpoint of safety and printing properties. Accordingly, it is preferred for the recording medium to have an ink accepting layer on the non-porous film, made of a hydrophilic substance. On the other hand, high water resistance and light resistance are required for the printed matters obtained by such recording, particularly for printed matters for display or exhibition inside or outside the buildings or automobiles. To satisfy such requirements, methods of laminating plastic films on such printed matters, have been proposed, for example, in Japanese Unexamined Patent Publications No. 56184/1987, No. 59076/1987, No. 60683/1987, No. 202794/1987, No. 273889/1987, No. 273890/1987, No. 280085/1987 and No. 280086/1987.
However, such conventional laminating methods had difficulties such that the color development was inadequate, and when the laminated film and the printed matter were of the same size, or when a necessary portion was cut after the lamination, sealing along the edge was difficult, and it was difficult to prevent a problem such that water penetrated from the edge tends to blot the printed image.
Further, Japanese Unexamined Patent Publications No. 161583/1987 and No. 280086/1987 disclose a method in which an acrylic resin or paraffin wax is coated on a printed image. However, this method can hardly be said to be practically acceptable.